Cutting tool with chip breaker



Dec. 29, 1970 Y ARMSTRONG ETAL 3,550,230

' CUTTING TOOL WITH can BREAKER Filed Aug. 21, 1968 ITEM \\\ Illllllfedora! firm/05 660 e .H ,vpe j M iv aria United States Patent 3,550,230CUTTING TOOL WITH CHIP BREAKER Harold F. Armstrong, Milford, and GeorgeL. Huppe,

Manchester, N.H., assignors to The UK. Tool Company Inc., Milford, N.H.,a corporation of New Hampshire Filed Aug. 21, 1968, Ser. No. 754,395Int. Cl. B26d 1/00 U.S. CI. 2996 3 Claims ABSTRACT OF THE DISCLOSURE Atool comprising a bit having cutting edges meeting at a corner, a chipbreaker and means for adjusting the breaker transversely of each edge.

Objects of the present invention are to provide simple and convenientmeans for adjusting chip breaker width, that is the distance between theedge of the chip breaker and the corresponding edge of the cutting bit,to accommodate different metals, different depths of cut, etc.,particularly for use in tools of the cartridge type with throwaway bits,

According to the present invention the tool comprises a bit holderhaving a bit seat, a bit supported on the seat with cutting edgesextending transversely of each other and projecting from the holder, achip breaker seating on the bit, a clamp for holding the bit and chipbreaker on said seat, and means carried by said clamp for adjusting thechip breaker transversely of one or both of said edges. Preferably saidadjusting means comprise screws threaded into the clamp approximatelyparallel to said seat, and said holder has shoulders engageable with thesides of the chip breaker which face away from said cutting edges.

In a more specific aspect the tool has a fastener extending through aslot in the clamp and threading into the holder, the slot extendingtransversely of one of said edges, and said adjusting means comprises ascrew threaded into said clamp from the side next to said one edge andbearing against said fastener, the clamp having a shoulder abutting thechip breaker on the side opposite said one edge. Preferably saidshoulder includes a lug which extends from the side of the holderadjacent said other cutting edge, and the tool has a second screwthreaded through the clamp from the side opposite the other of saidedges and bearing against the chip breaker to push it toward the otheredge.

For the purpose of illustration a typical embodiment of the invention isshown in the accompanying drawings in which FIG. 1 is a view from oneside;

FIG. 2 is a view from the opposite side;

FIG. 3 is a plan view;

FIGS. 4 and 5 are sections on lines 4--4 and 55 of FIG. 1; and

FIG. 6 is a bottom plan view of the clamp.

The particular embodiment of the invention chosen for the purpose ofillustration comprises a bit holder 1 of conventional type having aright angle recess for a square bit 2 also of conventional type. In therecess is a hardened seat 3 for the bit held in place by a screw 4. Eachof the r 3,550,230 1C6 Patented Dec. 29, 1970 four sides of the bit hasa cutting edge and any two adjacent edges may project beyond the holderto serve as cutting edges as shown at 5 and 6. Seating on the bit is achip breaker 7 having sloping sides adjacent the edges 5 and 6 to breakthe chips cut by these edges. The bit and breaker are held in place by aclamp 8 fastened by a screw 9 extending through a slot 11 in the clampand threading into the holder. At its rear end the clamp has acylindrical foot 12 seating on the holder and at its front end thebottom of the clamp has a right angle recess with sides 13 and 14forming shoulders facing the sides of the chip breaker opposite thecutting edges 5 and 6 respectively (FIG. 6). As shown in FIGS. 5 and 6the clamp 8 has a projecting lug 17 to extend the shoulder 14 somewhatbeyond the recess.

According to this invention the chip breaker is adjusted transversely ofthe cutting edge 5 by a screw 15 and transversely of the cutting edge 6by a screw 16; the screws threading through the clamp transversely ofthe cutting edges. The inner end of screw 15 bears on the side of thechip breaker opposite the cutting edge 5 so that by threading the screw15 inwardly the chip breaker is pushed toward the cutting edge to reducethe chip breaker width at the edge 5. The inner end of screw 16 bears onthe screw 9 so that by threading it inwardly the shoulder 14 of theclamp pushes the chip breaker toward the cutting edge 6 to reduce thechip breaker width at that edge. After the two chip breaker widths areadjusted as desired the screw 9 is tightened to clamp the breaker inadjusted position.

We claim:

1. A tool comprising a bit holder having a seat for abit, a bitsupported on said seat with cutting edges extending transversely of eachother and projecting from the holder, a chip breaker seating on the bit,a clamp for holding the bit and chip breaker on said seat, first meanscarried by said clamp for adjusting the chip breaker transversely of oneof said edges, and second means carried by the clamp for adjusting thechip breaker transversely of said other edge. u

2. A tool according to claim 1 wherein said adjusting means are screwsthreaded into the clamp approximately parallel to said seat.

3. A tool according to claim 1 further characterized by a fastenerextending through a slot in the clamp and threading into the holder, theslot extending transversely of one of said edges, and said adjustingmeans comprises a screw threaded into said clamp from the side next tosaid one edge and bearing against said fastener, the clamp having ashoulder facing the chip breaker on the side opposite said one edge, anda second screw threaded through the clamp from the side opposite theother of said edges and bearing against the chip breaker to push ittoward the other edge.

References Cited UNITED STATES PATENTS 2,693,019 11/1954 Greenleaf 29962,860,402 11/ 1958 Proksa 2996 2,897,580 8/1959 Huber 2996 3,113,37212/1963 Hargreaves 2996 3,187,407 6/1965 Ducet 29-96 HARRISON L. HINSON,Primary Examiner

